Fluorinated surfactants have been widely used in a variety of applications (e.g., coatings, stripping compositions, and emulsion polymerizations) for many years. The addition of a fluorinated surfactant to a formulation (e.g., a coating formulation or stripping formulation) may enhance the properties of the formulation by improving, for example, wetting behavior, leveling properties, and storage stability (e.g., with respect to phase separation). The particular properties affected depend, for example, on the particular composition of each surfactant and the particular formulation.
In coating applications, surfactants that are useful leveling agents lower the surface energy of a formulation and maintain that surface energy at a nearly constant value during drying. However, in general, the ability of a surfactant to lower the surface tension of a solvent or formulation (i.e., the surfactant strength) has little predictive value in determining whether that surfactant will function well as a leveling agent in a coating formulation.
Traditionally, many widely used fluorinated surfactants include long-chain perfluoroalkyl groups, (e.g., perfluorooctyl groups). Recently, however, there has been an industry trend away from using perfluorooctyl fluorinated surfactants, which has resulted in a desire for new types of surfactants which may be used in a variety of applications.